#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=2e5+100;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
char str[maxn];
LL a[maxn],tot=0;
int main(void)
{
  cin.tie(0);std::ios::sync_with_stdio(false);
  LL t;cin>>t;
  while(t--){
    LL n;cin>>n;
    for(LL i=0;i<n+10;i++) a[i]=0,tot=0;
    cin>>(str+1);
    for(LL i=1;i<=n;i++){
        if(str[i]!=str[i-1]) a[++tot]=1;
        else a[tot]++;
    }
    LL now=1;LL sum=0;
    for(LL i=1;i<=tot;i++){
        while(now<=tot&&a[now]==1) now++;
        sum++;
        if(now<=tot){
            a[now]--;
        }
        else{
            i++;
        }
        if(i==now) now++;
    }
     cout<<sum<<"\n";
  }
return 0;
}
